Rotary connector for flexible elongate member having electrical properties

ABSTRACT

Rotary connector for use with a flexible elongate member having electrical properties and having a proximal extremity with at least first and second conductive spaced-apart sleeves provided thereon. A housing is provided having a bore therein. First and second spaced-apart conductive disks are disposed in said bore. The disks are adapted to have the proximal extremity of the flexible elongate member extend therethrough and to have the conductive sleeves be in contact with the conductive disks while permitting rotation of the flexible elongate member, a push button clamping assembly is carried by the housing for retaining the proximal extremity of the flexible elongate member in the housing. Leads are connected to the conductive disks.

This is a division of application Ser. No. 08/114,767 filed Aug. 31,1993, now U.S. Pat. No. 5,358,409.

This invention relates to a rotary connector for a flexible elongatemember having electrical properties and more particularly to a rotaryconnector for a flexible elongate member having electrical propertiesand having a proximal extremity with at least first and secondconductive sleeves provided thereon.

In patent application Ser. No. 07/904,831, filed on Jun. 26, 1992, nowU.S. Pat. No. 5,240,437, issued Aug. 31, 1993, there is disclosed atorquable guide wire assembly with electrical functions which isprovided with a rotary connector. With such a rotary connector, it hasbeen found that on occasion when contamination is present, as forexample a blood or saline solution, there is a tendency for intermittentelectrical contact to occur. There is therefore need to overcome suchpossible intermittent contact and to ensure continuous contact.

In general, it is an object of the present invention to provide a rotaryconnector for use with a flexible elongate member having electricalproperties which provides a consistent electrical contact.

Another object of the invention is to provide a connector of the abovecharacter which provides very low friction against rotation of theflexible elongate element.

Another object of the invention is to provide a connector of the abovecharacter in which the proximal extremity of the flexible elongateelement can be readily inserted and removed.

Another object of the invention is to provide the connector of the abovecharacter which includes means for retaining the proximal extremity ofthe flexible elongate member in the connector.

Additional objects and features of the invention will appear from thefollowing description in which the preferred embodiments are set forthin detail in conjunction with the accompanying drawings.

FIG. 1 is a side-elevational view of a rotary connector incorporatingthe present invention and having a flexible elongate member mountedtherein.

FIG. 2 is longitudinal cross-sectional view of the connector shown inFIG. 1.

FIG. 3 is a cross-sectional view taken along the line 3--3 of FIG. 1.

FIG. 4 is a cross-sectional view taken along the line 4--4 of FIG. 1.

FIG. 5 is an exploded isometric view of the rotary connector shown inFIG. 1.

In general, the rotary connector incorporated in the present inventionis for use with a flexible elongate member having electrical propertiesand having a proximal extremity with at least first and secondconductive sleeves provided thereon. An outer housing is provided whichhas a bore therein. First and second spaced-apart conductive disks aremounted in the bore. The conductive disks are sized so that theconductive sleeves can extend therethrough and make electrical contacttherewith. Leads are coupled to the conductive disks. A grippingmechanism is carried by the housing for retaining the proximal extremityof the flexible elongate member in the housing.

More in particular, as shown in the drawings, the rotary connector 11 isadapted to be used with a flexible elongate member 12 which can be inthe form of a guide wire. The flexible elongate member 12 is providedwith a shaft 13 formed of a stainless steel hypotube and having proximaland distal extremities 16 and 17. A coil spring 21 is mounted on thedistal extremity 17 and is secured thereto. It carries a housing (notshown) which carries an electrical device 23 such as an ultrasonictransducer. Conductors (not shown) are connected to the electricaldevice 23 such as to the front and back sides of the ultrasonictransducer 23 and extend through the coil spring 21 and through theshaft 13 to the proximal extremity and are connected to first and secondconductive sleeves or slip rings 26 and 27.

The rotary connector 11 consists of a shell or outer housing 31 which iscylindrical in shape which is provided with a bore 32 extendingtherethrough up to a dam 33. The dam 33 has a centrally disposed hole 34therein. A multistage inner housing 35 is mounted within the shell 31.The outer housing 31 and the multistage inner housing 35 are formed of asuitable material such as plastic. The multistage inner housing 35consists of a first stage 36, a second stage which consists of twopieces 37 and 38 and a third stage 39.

The first stage 36 is formed of a solid piece and is provided with anannular recess 41. It is also provided with a chamfered hole 42extending therethrough which is sized so that it is adapted toaccommodate the proximal extremity of the flexible elongate member 12which can be considered to be a male connector. A chamfer or countersink43 is provided at the commencement of the hole 42 to facilitate theintroduction of the proximal extremity of the flexible elongate member12 therethrough. The first stage 36 has a diameter such that it can beintroduced into the bore 32 of the shell or outer housing 31 with thehole 42 being axially aligned with the axis of the housing 31.

The second stage pieces 37 and 38 are also formed of a solid materialand are provided with bores 47 on the distal ends and annular recesses48 on the proximal ends and slots 49 extending into the bores 47 asshown particularly in FIG. 5 with the slot 49 in piece 37 being offsetcircumferentially with respect to the slot 49 in piece 38 by a suitableangle such as 120°. Chamfered holes 51 extend axially of the secondstage pieces 37 and 38. The bores 47 and the annular recesses 48 aresized so that the second stage pieces 37 and 38 can be nested and seatedin the bore 32 of the housing 31 as shown in FIG. 2.

The third stage 39 is also formed of a solid piece and is provided witha central bore 52 and is also provided with three circumferentiallyspaced apart slots 54 spaced 120° apart. The bore 52 is sized so thatsecond stage piece 38 can seat in the bore 52. A plurality ofcircumferentially spaced-apart slots 54 spaced approximately 120° apartare provided in the third stage 39 and extend longitudinally thereof andopen into the annular recess 52. A chamfered hole 56 extends through thethird stage 39 and is axially aligned with the chamfered holes 51 insecond stage pieces 37 and 38. The plastic which is used for the variousparts of the rotary connector 11 can be of a suitable type such as ABS.

Conductive disks 61 are provided which are adapted to be mounted in thebores 47 of the second stage pieces 37 and 38 and in the bore 52 of thethird stage 39. Each of the conductive disks 61 consists of a conductivemetal ring 62 formed of a suitable material such as brass which isprovided with an integral tab 63 and has a centrally disposed opening 64therein. A conductive elastomeric membrane 65 is vulcanized to the ring62 and extends across the opening 64 in the ring. One conductiveelastomeric material found to be satisfactory is an electricallyconductive silicon rubber identified as X-65-101U supplied by thePerformance Elastomers division of Furon, 1032 Morse Avenue, Sunnyvale,Calif., 94089. Such an elastomer has a Shore A hardness of 58, a tensilestrength of 250 psi, elongation of 200%, a volume resistivity in ohm-cmof 0.006 and a tear strength of 60 psi. It is desirable that theconductivity of the material used for the membrane be very high so as tomake excellent electrical contact with the conductive slip ring when itis disposed in the membrane. Thus it can be less than 0.006 ohm-cm. Thematerial should not be brittle but it should be flexible enough so thatit can withstand puncturing without ripping or tearing. Typically themembrane before vulcanization can have a thickness ranging from0.005-0.040 inches and preferably ranging from 0.025-0.030 inches. Thering 62 itself can have an outside diameter of a suitable size, as forexample 0.25 inches. If desired, a small centrally disposed hole 66 canbe provided in each of the membranes 65 through which the proximalextremity 16 of the flexible elongate member 12 can pass. It isdesirable that this hole have a diameter which is smaller than thediameter of the conductive sleeves or slip rings 26 so that anelastomeric fit will occur between the membrane 65 and the slip ring 26when it is disposed therein to provide good conductivity with the slipring.

Conductors 71 are provided which are connected to the tabs 63 of theconductive rings 62, which tabs are aligned with one of the slots 49with the conductors extending proximally therefrom through the slots 49and the slots 54. The conductors 71 extend proximally and are connectedinto a cable 73 which extends through a strain relief such as cable clip77 mounted within a flanged end cap 76. The cable 73 extends through theend cap 76 and is connected to a fitting 74 (see FIG. 1) which isadapted to be connected to electronic equipment (not shown).

The conductive disks 61 are adapted to be disposed within the bores 47and 52 and are retained therein with the tabs 63 being aligned with oneof the tabs 63 being disposed in each of the circumferentiallyspaced-apart slots 49 and 54. All of the stages can then be assembledinto a single unit and then placed within the outer housing or shell 31followed by the cable 73 and the cable clip 77 and the end cup 76 toclose off on one end of the outer housing or shell 31. Means is carriedby the outer housing 31 for retaining the proximal extremity of theflexible elongate member 12 in a fixed longitudinal position within theouter housing or shell 31 after the proximal extremity 16 has beenpositioned in the conductive disks 61 disposed within the outer housingor shell 31. This means takes the form of a push button grip mechanism81. It consists of a spindle 82 formed of a suitable material such asplastic which is provided with a cylindrical extension 83 of reduceddiameter which is adapted to fit in a bore 84 within the distalextremity of the outer housing or shell 31 on the other side of the dam33. In order to reduce the friction during rotation of the spindle 82the cylindrical extension 83 is spaced from the dam 33 and is providedwith rounded circumferentially spaced-apart protrusions 85 which areadapted to be seated within and travel in an annular groove 86 providedin the interior wall forming the bore 84 of the outer housing 31. Thespindle 82 is provided with an oval-shaped rounded depression 87. Acylindrical recess or well 88 which can be rectangular in cross sectionextends into the spindle 82 diametrically thereof and opens through thedepression 87. A push button 89 is disposed within the recess 88. Thepush button 89 has an outer extremity which is in the form of a squareprism shape disposed in the depression 87 to aid in sensing the pushbutton 89 by a finger of the hand without slipping of the finger of thehand on the push button.

Means is provided for retaining the push button 89 within the recess 88but permitting axial movement of the push button in the recess 88 andconsists of first and second dowel pins 91 and 92 extending through theholes 93 and 94 in spindle 82 and having their inner extremitiesdisposed in longitudinally extending recesses 96 provided in oppositesides of the push button 89. An elongate hole 97 is provided in the pushbutton and extends longitudinally of the push button. The elongate hole96 is in alignment with a hole 98 extending at right angles thereto inthe spindle 82. Yieldable spring means is provided within the well 87and consists of a dish-shaped spring member 99 disposed in the well orrecess 88 and engaging the innermost extremity of the push button 89.The distal extremity of the spindle 82 is provided with a recess 101which is rectangular in cross section that is adapted to receive arectangular extension 102 provided on a front cap or nose piece 103. Thenose piece 103 is provided with a chamfered hole 106 which is inalignment with the hole 96 and also in axial alignment with the hole 97in the spindle 82.

Operation and use of the rotary connector 11 in connection with theflexible elongate member 12 may now be briefly described as follows. Letit be assumed that it is desired to utilize a flexible elongate member12 such as a guide wire 12 in connection with an angioplasty procedure.Let it also be assumed that it is desired to advance the guide wirethrough the femoral artery into a vessel in the heart. The guide wire 12is advanced in a conventional manner until it is near the heart.Thereafter to advance the guide wire 12 into a vessel of the heart, itis often desirable to provide means to provide rotation of the guidewire. When this is desirable, the rotary connector 11 of the presentinvention can be utilized. The proximal extremity 16 of the guide wire12 can be introduced into the chamfered hole 106 provided in the nosepiece 103. The proximal extremity 16 is then advanced through theelongate hole 96. While depressing the push button 89 the proximalextremity 16 is advanced through the hole 97 and thence into the hole 42in the first stage 36, and thence through the membrane 65 of the firstconductive disk 61, thence through the hole 51, thence through the nextconductive disk 61 through the hole 51, thence through the lastconductive disk 61, thence through the hole 56 in the third stage 39 anduntil it is seated at the bottom of the hole 56. The slip rings 26 and27 are then in alignment with the conductive disks 61 and makeelectrical contact therewith through their conductive membranes 65 andthrough the conductive ring 62 to the conductors 71 and thence into thecable 73 and the connector 74. One of the disks 61 makes contact withshaft 13 to form a ground connection.

As soon as the proximal extremity 16 has been firmly seated within therotary connector 11, the push button 89 can be released to permit thespring member 99 to urge the button 89 upwardly to have the bottom ofthe hole 97 engage the proximal extremity 16 and to clamp it against theholes 106 and 98. Thereafter, the spindle 82 can be rotated to rotatethe flexible elongate element 12 to any desired angular position whilestill maintaining electrical contact therewith through the conductivedisks 61.

The guide wire can then be advanced and rotated until the distalextremity has been advanced into the desired location in the bloodvessel. In connection with the procedure, if it is necessary to use anexchange wire, the rotary connector 11 can be readily removed bydepressing the push button 89 to release the proximal extremity 16 ofthe flexible elongate member 12 to permit the same to be removed. Anexchange wire can then be affixed thereto. Thereafter, the angioplastyprocedure can be completed in a conventional manner.

From the foregoing it can be seen that there has been provided a rotaryconnector which provides continuous electrical contact with the sliprings during rotation of the flexible elongate member even in thepresence of contamination. It is relatively simple and is easy tooperate and can be operated by one hand with the finger depressing thepush button while permitting use of the other hand to insert theproximal extremity of the guide wire into the rotary connector.

What is claimed is:
 1. A grip mechanism in a rotary connector for usewith a flexible medical guide wire, comprising a member having atransversely extending well disposed therein, a push button mounted inthe well for movement transversely of the member, cooperative means inthe push button and in the member permitting limited movement of thepush button relative to the well and yieldable means disposed in thewell yieldably urging the push button out of the well, said push buttonhaving the hole therein extending transversely of the direction ofmovement of the push button in the well, said member having a holetherein extending in a direction parallel to the hole in the pushbutton, the push button being movable by depression of the push buttonagainst the force of the yieldable means so that the hole in the pushbutton is moved into axial alignment with the hole in the member wherebywhen the flexible elongate element is inserted into the hole in themember and the hole in the push button while the push button isdepressed, the push button when released will clamp the flexibleelongate element between the push button and the member.